Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-22T11:56:43.849Z Has data issue: false hasContentIssue false

Kaolinization of Bauxite: A Study of the Vlasenica Bauxite Area, Yugoslavia. II. Alteration of Oolites

Published online by Cambridge University Press:  02 April 2024

Adam Dangić*
Affiliation:
Faculty of Mining & Geology, University of Belgrade, Djusina 7, 11000 Belgrade, Yugoslavia
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

During the epigenetic alteration of boehmitic karstic bauxite in the Vlasenica region of Yugoslavia, which was caused by siliceous water descending through the deposit by means of cracks, fissures, etc., oolites were less altered compared with the coexisting matrix material, which was intensely kaolinized. The following zonal alteration pattern of the oolites was identified: a diaspore enrichment zone, followed by a diaspore-boehmite enrichment zone, and then the original bauxite. Considering this alteration pattern and that determined previously for the matrix material, the following overall pattern of alteration was established: a kaolinite-diaspore zone, followed by a boehmite-diaspore zone, and then the original bauxite. The alteration solutions reacted with the bauxite to form solution-matrix and solution-oolite subsystems, which were characterized by different types of diffusion and geochemistry.

In the kaolinite-diaspore zone Si-metasomatism kaolinized the matrix, and excess Al partly migrated into the oolites, forming diaspore, and outward into the bauxite. The latter Al-remobilization resulted in a transition zone, in which new boehmite was formed in both the matrix and the oolites, and diaspore only in the oolites. Thermodynamic models of oolites and whole bauxite alterations were established, on the basis of stability diagrams calculated for the mineral assemblages of both the oolites and the matrix, in the alteration zones and in the deposit as a whole. Based on these models, the genesis of the diaspore and the relationship of diaspore-boehmite-kaolinite assemblages in natural systems at low temperature and low pressure can be described.

Rezime

Rezime

Tokom epigenetske alteracije bemitskih karsnih boksita u području Vlasenice, izazvane perkolacijom voda obogaćenih rastvorenom silicijom koje su ponirale kroz pukotine, rasedne zone i si., ooliti su slabije alterisani u poredjenju sa koegzistentnom osnovom koja je intenzivno kaolinisana. Identiflkovan je sledeći tip zoname alteracije za oolite: zona obogaćenja dijasporom, iza koje siede zona obogaćenja dijasporom i bemitom i zatim originalní boksit. Na osnovu razmatranja ovog tipa alteracije i tipa alteracije za materijal osnove, ustanovljen je sledeći tip alteracije boksita kao celine: kaolinitsko-dijasporska zona, iza koje siede bemitsko-dijasporska zona i zatim originalni boksit. Alteracioni rastvor je reagovao sa boksitom obrazujući kompleksan sistem, koji se sastojao od dva podsistema: rastvor-materijal osnove i rastvor-ooliti, koji su se medju sobom razlikovali kako po modelima difuzije tako i po geohemijskim karakteristikama.

U kaolinsko-dijasporskoj zoni Si-metasomatizam je doveo do kaolinizacije materijala osnove, a višak Al je delom migrirao kako u koegzistentne oolite, obrazujući u njima dijaspor, tako i dublje u boksit. Remobilizacija Al dublje u boksit dovela je do obrazovanja prelazne zone, u kojoj se obrazovao bemit i u osnovi i u oolitima, i dijaspor samo u oolitima. Postavljeni su termodinačički modeli za alteraciju oolita i boksita kao celine, a na osnovu dijagrama stabilnosti proračunatih za mineralne asocijacije i oolita i osnove, u zonama alteracije i u samom ležištu. Na osnovu svega ovoga razmotreni su tačnije i pouzdanije geneza dijaspora i odnos dijaspor-bemit-kaolinit u prirodnim sistemima na niskim temperaturama i niskim pritiscima.

Type
Research Article
Copyright
Copyright © 1988, The Clay Minerals Society

References

Bárdossy, G., 1982 Karst Bauxites—Bauxite Deposits on Carbonate Rocks Amsterdam Elsevier 441.Google Scholar
Beneslavsky, S. I., 1963 Mineralogy of Bauxites Moscow Gosgeoltekhizdat 170.Google Scholar
Beneslavsky, S. I., 1968 Basic features of unity of the process of minerogenesis in lateritic and sedimentary bauxites Travaux du ICSOBA 5 416.Google Scholar
Bushinsky, G. I., 1968 Case of natural bleaching of bauxites Travaux du ICSOBA 5 1730.Google Scholar
Combes, P.J., 1969 Recherches sur la genèse dans le Nord-Est de l’Espagne, le Languedoc et l’Ange (France) Mém. Centre Étude Rech. Géol. Hydrogéol. Montpellier 342.Google Scholar
Dangić, A., 1983 Kaolinization of bauxite—A study in the Vlasenica bauxite-bearing area, Yugoslavia Abstracts, 5th ICSOBA Congress, Zagreb, Yugoslavia 12.Google Scholar
Dangić, A., 1984 Synthesis of jarosite, ferrihydrite, goethite, and other ferrioxide minerals from ferrosulfate solution C. R. Séances Soc. Serbe Géol. 1983 107113.Google Scholar
Dangić, A., 1985 Kaolinization of bauxite—A study in the Vlasenica bauxite area, Yugoslavia. I. Alteration of matrix Clays & Clay Minerals 33 517524.CrossRefGoogle Scholar
Dangić, A., 1985 Epigenetic diaspore in the Vlasenica bauxite region of Yugoslavia—Appearance and genesis Abstracts, Int. Symp. Bauxite Prospect. Mining, Tapolca, Hungary 19.Google Scholar
Ervin, S Jr and Osborn, E. F., 1951 The system Al2O3-H2O J. Geol. 59 381394.Google Scholar
Fox, G. S., 1932 Bauxite and Aluminous Laterite London Technical Press 312.Google Scholar
Garrels, R. M. and Christ, C. L., 1965 Solutions, Minerals and Equilibria New York Harper and Row 450.Google Scholar
Gladkovsky, A. K., Ushatinsky, I. N. and Karšulin, M., 1964 Genesis and alteration of aluminous minerals in bauxites Simp. Bauxites, Oxides et Hydroxides d d’Aluminium, Zagreb, 1963, Vol. 1 Zagreb Academie Yougoslave Sci. Arts 153170.Google Scholar
Goldman, M. I., 1955 Petrography of bauxite surrounding a core of kaolinized nepheline syenite in Arkansas Econ. Geol. 50thAniv. 586609.CrossRefGoogle Scholar
Goldman, M. I. and Tracey, J. I. Jr., 1964 Relation of bauxite and kaolin in the Arkansas bauxite deposits Econ. Geol. 14 567575.Google Scholar
Gorecky, Y. K., Lavrovich, N. S. and Lyubimov, A. B., 1949 Bauxites Moscow Gosgeoltekhizdat 186.Google Scholar
Hemingway, B. S., Robie, R. A. and Kittrick, J. A., 1978 Revised values for the Gibbs free energy of formation of (Al(OH) 4 aq), diaspore, boehmite and bayerite at 298.15 K and 1 bar, the thermodynamic properties of kaolinite to 800 K and 1 bar, and the heats of solution of several gibbsite samples Geochim. Cosmochim. Acta 42 15331543.CrossRefGoogle Scholar
Keller, W. D., 1962 The Principles of Chemical Weathering Missouri Lucas Brothers Publ., Columbia 111.Google Scholar
Keller, W. D. and Clarke, O. M. Jr., 1984 Resilication of bauxite at the Alabama Street Mine, Saline County, Arkansas, illustrated by scanning micrographs Clays & Clay Minerals 32 139146.CrossRefGoogle Scholar
Keller, W. D. and Stevens, R. P., 1983 Physical arrangement of high-alumina clay types in a Missouri clay deposit and implications for their genesis Clays & Clay Minerals 31 422434.CrossRefGoogle Scholar
Kennedy, G., 1959 Phase relations in the system Al2O3-H2O at high temperatures and pressures Amer. J. Sci. 257 563573.CrossRefGoogle Scholar
Kiskyras, D., Chorianopoulou, P., Papazeti, H. and Augustithis, S. S., 1978 Some remarks about the mineralogical composition of the Greek bauxites Proc. 4th Int. Congress Study Bauxite, Alumina, and Aluminum, Athens, 1978, Vol. 1 Athens Natl. Tech, University 409433.Google Scholar
Kittrick, J. A., 1969 Soil minerals in the Al2O3-SiO2-H2O system and a theory of their formation Clays & Clay Minerals 17 157167.CrossRefGoogle Scholar
Komlóssy, G., 1976 Minéralogie, géochimie et génétique des bauxites du Vietnam du Nord Acta Geol. Acad. Sci. Hungary 20 199244.Google Scholar
Maynard, B. J., 1983 Geochemistry of Sedimentary Ore Deposits New York Springer Verlag 305.CrossRefGoogle Scholar
Naumov, B. N., Ryzhenko, B. N. and Khodakovsky, I. L. (1974) Handbook of Thermodynamic Data: I. Barnes and V. Speltz, eds., U.S. Geol. Surv., p. 328 (translation from Russian).Google Scholar
Nia, R., 1968 Zur Bedeutung der methodishen Probennahme für genetische Untersuchungen von Bauxit-Lagerstätten am Beispiel der Oberkreide-Bauxite der Parnass-Kiona Zone Griechlands Min. Deposita 3 368374.CrossRefGoogle Scholar
Özlü, N., 1985 New facts on diaspore genesis in the Akseki-Seydisehir bauxite deposit (Western Taurus, Turkey) Travaux du ICSOBA 14–15 5362.Google Scholar
Perkins, D 3rd Essenc, E. J., Westrum, E. F. Jr. and Wali, V. J., 1979 New thermodynamic data for diaspore and their application to the system Al2O3-SiO2-H2O Amer. Mineral. 64 10801090.Google Scholar
Valeton, I. and Amstutz, G. C., 1964 Problems of boehmitic and diasporic bauxites Sedimentology and Ore Genesis Amsterdam Elsevier 123129.CrossRefGoogle Scholar
Valeton, I., 1965 Faciesprobleme in südfranzösischen Bauxitlagerstätten Beitrage Mineral. Petrogr. 11 217246.Google Scholar
Valeton, I., 1972 Bauxites Amsterdam Elsevier 226.Google Scholar